What is the reason for the lack of brightness of the outdoor LED full-color display? According to the years of experience of LED electronic display manufacturers, it is concluded that the following three factors can lead to the brightness inconsistency of the full-color LED display screen.
1. Luminous element
LED full color display luminescent element is LED luminescent tube, in the production process brightness inconsistency is inevitable. But the LED electronic display manufacturers adopt countermeasure is in produce after the completion of the step, the smaller the luminance difference between two gears, the consistency, the better, but can form the yield of the more severe the appearance of low and high inventories. As a result, each manufacturer has control of the two adjacent levels of brightness at 20%.
2. Drive element
LED full-color display drivers are usually constant current drive chips such as MBl5026. Inside these chips including 16 output constant current driver, can use resistance setting current output values, the same chip control error within 3% of each output of different chip output error control within 6%. LED full-color displays 25% between each pixel brightness error is normal, if use the LED luminous tube is not the same level, type of full-color LED display, can make the brightness error rose to more than 40%.
In addition it is important to note that full color LED display brightness, is the basic reason, forming flower screen can't use correct late check equipment, with a LED display manufacturer produces in the process of manufacturing. Therefore, please contact your service provider or manufacturer for a screen that is inconsistent in brightness.
3. The display screen is mixed in the production process, with different batches of points.
How to solve the color of LED electronic display?
Current through the LED the first method: is to change, general LED tube allows continuous working current is controlled in 20 ma, besides red leds have saturation phenomenon, other LED brightness basically proportional to the flow of electric current;
The second method: by using the human visual inertia, using pulse width modulation method to realize gray scale control, which is periodic change light pulse width (duty cycle), as long as the repetition of the light cycle is short enough (that is, the refresh rate is high enough), the human eye is feeling less than glowing pixels in jitter. Due to the pulse width modulation is more suitable for digital control, so widely used in microcomputer to provide LED display content today, almost all the LED electronic display is controlled by pulse width modulation to grayscale.